Love Hidden Burger. It's located in the back of the bottom line (you actually need to go through the bar to the very back) and it has a very cool archie comic aesthetic. Everything is cooked fresh in front of you while you wait.
I'm a vegetarian so I get the veggie burger with cheese when I go. Love the mixture and how it's cooked. It's a bit mushy which I love. It's not trying to be a beef burger like other burger joints that use simulated beef tasting soy that ends up tasting dry and bland. This real vegetable and bean patty is the best kind of veggie burger in my books. It's flavourful and not trying to be something it's not!
Burgers are smaller than standard pub fare and I find it the perfect amount for a lunch and I'm a 6'2" guy. I'm always the exact right amount of full after a combo. Toppings are well selected for that classic taste, fries are crispy, and jalapeno aioli is a great 50 cent addition to your order! (would love a chipotle aioli option too though)
I've taken two of my omnivore coworkers there already on different occasions and they had really good things to say about the beef burgers as well.